PROGRAM TITLE: Quantitative Links Research ACTIVITY STREAM: Processes SCIENCE ELEMENT:Climate and Hydrological System, Biogeochemical Dynamics DEPARTMENT OF ENERGY DESCRIPTION: Objectives of the Quantitative Links research program are to establish the relationships among atmospheric processes, changes in radiative fluxes, and/or changes in local temperature and long-term changes in global temperature (or other changes in climate). A broad range of research on the linkages between changes in atmospheric composition and global change is conducted. Measurements to quantify the relationship are the primary focus. The research is entering the fourth year of a five program and has completed a mid-term technical peer review. Research includes measurements and characterization of cloud condensation nuclei for climate model development, methane flux measurements from peat bogs, and laboratory measurements of aerosol optical properties. Statistical analyses of the climatic data are also conducted. Each project addresses an uncertainty in the quantification of the link between increasing greenhouse gases and global climate change. The research is therefore highly relevant to cause and effect linkages related to greenhouse gas policy issues. STAKEHOLDERS: The national and international measurement, modeling, and integrated assessment communities require specific data on atmospheric processes to reduce scientific uncertainty and establish the link between increasing greenhouse gases and global change. The Quantitative Links research provides such critical data. For example, the program provides data to assess the potential increase in atmospheric methane from selected human-influence and natural sources; cloud optical characteristic for ARM; process parameterizations for CHAMMP; and analyses of the climatic record as a forecast tool for future climate change. SHORT-TERM POLICY PAYOFFS: The research is directly relevant to the central question of cause and effect. The Quantitative Links program was designed to provide information into the science and policy process within five years of initiation. The methane data feeds directly into the data base for predicting future atmospheric concentration of greenhouses gases under scenarios of changing climate. The field experiments were conducted under "normal" and drought conditions. Initial analysis of the temperature observations over the last 100 years, indicates that the data themselves are not a good forecaster of the future trend. This provides the integrated assessment researchers limits on use of the data as well as reenforces the need for improved predictive models. Such products directly contribute to both National assessments and to the IPCC. The knowledge base is and will be used in technical evaluations of greenhouse gas sources and sinks in relation to energy emissions and thus supports the National Energy Policy Act objectives. PROGRAM CONTACT:Michael R. Riches, DOE, ER-74, Washington, DC 20585, 301-903-3264